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Welcome to this week's episode of brainstorm, where we give you a glimpse into the world
of science, for Saturday, March 8th, 2014. I'm the gentleman physicist, filling in for
Jack this week. We begin with news from the world of material
science. Only a few weeks ago we talked about a breakthrough in artificial nano muscles
that showed incredible promise for small-scale robotics. Now an international team led by
UT Dallas has also created an impressive artificial muscle, but from an unlikely material. While
the previously covered artificial muscles were made from a new kind of metal alloy with
impressive phase change properties, the ones were talking about today are made from...
Well, fishing line. If you're thinking it can be that simple, you're right, it also
incorporates sewing thread. As it turns out, the polymer in fishing line can also undergo
some dramatic changes due to temperature change. By coiling strands of this polymer in certain
ways the researchers were able to create artificial muscles that either rotated, contracted up
to 50% or expanded. To put that into perspective human muscle only contracts by 20%, and these
fishing line muscles can produce approximately 100 times the mechanical force of human muscle,
per weight. The heat that powers these muscles can be provided by a chemical reaction, ambient
changes in temperature, or by passing current through a resistant material, such as metal
coated sewing thread. One application for this technology is small-scale movements such
as tools used in microsurgery and mechanical components of microfluidic devices. Scaling
up, the researchers think this has incredible applications for robotics and strong but versatile
exoskeletons. So apparently everything we need to build Iron Man can be found in a random
storage closet or hobby shop. Switching gears to a more serious story, from
the world of medicine. Engineers over at MIT have developed a new type of vaccine that
may allow for the prevention of diseases not possible before. To quickly review how vaccines
work, you're essentially exposing the immune system to a molecule found in a pathogen or
disease, in order to train your immune system to fight it before the fact. For certain diseases
this is extremely effective, especially when whole organisms can be used to trigger an
immune response. Using only fragments or specific antigens to trigger an immune response is
not usually as effective, but some pathogens are too complex or dangerous to use the entire
thing. However, no matter the type of vaccine, all of the action really happens in the lymph
nodes, which is home base for T cells and B cells. So they developed a way to deliver
antigen molecules directly to the lymph nodes. A blood protein called albumin naturally binds
to fatty acids and delivers them to lymph nodes, so they combined their active vaccine
molecules with a fatty acid. In experiments with mice they tested this technique using
molecules from ***, melanoma, and cervical cancer. All of which resulted in an extremely
strong immune response, especially compared to the molecules alone without the fatty acid.
Obviously much more research is needed, but this will hopefully expand the range of diseases
that vaccines can be developed for. Our final story is an update from the world
of chemistry. A collaboration between the Lawrence Berkeley and the Argonne national
laboratory has resulted in a new catalyst for use in fuel cells and hydrogen production.
As we have discussed before, the best catalyst for many electrochemical applications is platinum.
Unfortunately, platinum is incredibly expensive and rare, and the double unfortunately, many
of the applications of this catalyst would improve environmentally friendly technologies.
So a lot of research is going into materials that reduce or replace platinum and other
precious metals entirely. So these scientists started by examining nanoparticles made from
a nickel platinum alloy, but then took it one step further. They created dodecahedron
particles and then eroded away the interior, leaving a nanoscale metallic wire frame structure.
This both dramatically increase the surface area and decreased the amount of total materials
used, including the valuable platinum. We won't bother you with all the technical details
but they ended up being extremely effective catalysts, exceeding the department of energy's
goals for 2017, tenfold. And these hollowed out nanoparticles can be modified with relative
simplicity to either work in a fuel cell, or in the electrolysis of hydrogen gas. The
scientists hope to further develop this catalyst and begin implementing it in various technologies.
Well hope you enjoyed this episode. In reference to our first story, what random junk would
you make an exoskeleton out of? Let us know your thoughts on that and all the stories
in the comments.